PHILIPS LDH 5605/00
16 CAMERA VIDEO CONTROL SWITCHER
The camera switcher is the workhorse in any
multi-camera video surveillance system; its role, as the core component, is a
demanding one and requires total reliability, but when it comes to assembling
and installing a system, switchers frequently assume a secondary importance,
some way behind cameras and other, more high-profile ancillary devices.
The Philips LDH 5600 series video control
switchers (VCS) should help to elevate them to a more prominent position. To
begin with they don't look like typical switchers, which frequently seem to be
built from an assortment of randomly-sourced parts, in off-the-shelf instrument
cases. Moreover the flexibility and versatility of the various models in the
range means they can work within a wide variety of system configurations, from
small to medium scale installations in commercial and retail environments,
public buildings or industrial premises.
The four models are: LDH 5600/00, which has 8
video inputs, 2 video outputs and camera control facilities; LDH 5601/00 -- 8
video inputs, 2 video outputs, camera control and 8 alarm inputs; LDH 5604/00 --
16 video inputs, 2 video outputs and camera control; and the subject of this
month's 'Bench Test', the 5605/00
which has 16 video inputs, 2 video outputs, camera control and 16 alarm inputs.
All four share the same distinctive sloping, steel-cased console; this can be
free-standing, or flush-mounted in a desk.
The lower part of the front panel comprises a
membrane-type keypad, divided into three sections. The numbered buttons on the
bottom half are the camera selectors; the camera controls are on the right
side, they are for near/far focus, tele/wide zoom, pan/tilt, camera wiper and
two auxiliary functions. These facilities are all dependant on the camera being
fitted with an appropriate control unit, which connects to an interface socket
on the unit's back panel. The keys on the top row of the panel are for
selecting the monitor output, sequence start, VCR control and alarm reset.
Above the keypad there's a blank panel with a removable transparent cover; we
assume this space is for operator instructions or control labelling, though
this is not mentioned in the instructions.
The back panel is dominated by a bank of 16
BNC connectors; for the camera inputs; next to that there's a row of four BNCs
for the two monitor outputs and video in/out for a VCR. Below that are two
D-connectors; one 25-way socket for the alarm inputs and outputs, the second, a
9-way socket, carries camera control data (RS485 levels). Power is supplied by an external 12 volt DC
Philips have designed the 5605, and it's
stablemates so they can be used straight out of the box with a minimum of fuss,
but their real strength lies in the range of user-defined options and pre-sets
which are accessed via a multi-lingual, on-screen display system. Routine
displays include camera ident, status, video loss warnings, alarm triggering
and switchable time/date display (monitor B output only). The main set-up
display appears when the monitor 'A' key is held for more than five seconds.
This brings up the configuration index which has a number of options, including
composing camera idents (1-line, 24 characters), from a selection of 112
characters, it can be displayed at the top or bottom of the screen. Other
facilities include display style (black or white lettering on a grey or
transparent background); sequence and dwell timings (1-99 seconds) and alarm
configuration. Selecting any of the options calls up a sub-menu, with the
various parameters selected or engaged using the four camera pan/tilt keys. A
service menu, which monitors all of the unit's main functions, is displayed
when the VCR-enable button is depressed for more than five seconds
Alarm operation is fairly straightforward.
With the switcher in the 'Night' mode an input trigger sets off a warning
buzzer and the LED below the monitor B button starts to flash. Monitor output A
is automatically selected, the relevant camera output and ident are displayed,
and the VCR enable output is energised for one second. During sequencing if any
of the video inputs are interrupted or cut off a 'Video Absent' message is
displayed on the screen and the switcher returns to the previously selected
reliability the most critical aspect of a switcher's performance is it's
transparency to the video signals passing through it; any degradation could
result in a loss of vital evidential information. The 5605 scores well in this
respect and there's no increase in noise, or reduction in detail in colour or
monochrome signals. Reliability should be good, the standard of construction is
high, though our sample had some late, and not especially neat, modifications to the power supply section.
After that it boils down to how easy the system is to set-up and use.
set-up is reasonably simple, once the rather brief instructions have been
digested and programming procedures mastered. Some of the routines are rather unforgiving
and a momentary lapse of concentration will return the system to the main menu,
erasing any changes that may have been made. The graphic generator produces a
fairly crude display and some of the sub-menus, particularly those used for
configuring the sequencer and alarm installation are a little ambiguous in
places and could do with some tidying up.
however, the unit behave impeccably, though it appears to have only partial
memory backup. If the power supply is interrupted -- even for a moment -- the
sequencer stops and the clock resets, this could be a disadvantage during
Philips have obviously put a lot of thought
and effort into the design of the 5605, and generally speaking it works very
well indeed, but there are a couple of
flaws. The on-screen display system, whilst comprehensive is not
especially easy to use, or operator friendly, and its vulnerability to
power-cuts seems like an oversight. Those criticisms aside the 5605 would appear
to fill a sizeable niche in the market for a versatile and reasonably priced
switcher that can be used in a wide variety of applications.
design features ***
installation and wiring ****
variety of functions ****
advice and backup ****
R.Maybury 1993 1101